Mr Gilbert, however, was in.
Just.
He opened his front door to my ring and said whatever I wanted I would have to come back later, as he was just off to play golf. Clubs and a cart for transporting them stood just inside the door, and Mr Gilbert's heavy frame was clad appropriately in check trousers, open-necked shirt and blazer.
'It's about Liam O'Rorke's betting system,' I said.
'What?' he said sharply.
'Mrs O'Rorke asked me to come. She says she might be able to sell it to you after all.'
He looked at his watch; a man of about fifty, in appearance unimpressive, more like a minor official than a peddlar of pinchbeck dreams.
'Come in,' he said. 'This way.'
His voice was no-nonsense middle-of-the-road, nearer the bingo hall than Eton. He led me into an unexpectedly functional room furnished with a desk, typewriter, wall maps with coloured drawing pins dotted over them, two swivel chairs, one tray of drinks and five telephones.
'Fifteen minutes,' he said. 'So come to the point.' He made no move to sit down or offer me a seat, but he was not so much rude as indifferent. I saw what Mrs O'Rorke had meant about him being a cold man. He didn't try to clothe the bones of his thoughts with social top-dressing. He'd have made a lousy schoolmaster, I thought.
'Liam O'Rorke's notes were stolen,' I began.
'I know that,' he said impatiently. 'Have they turned up?'
'Not his notes, no. But computer programs made from them, yes.'
He frowned. 'Mrs O'Rorke has these programs?'
'No. I have. On her behalf. To offer to you.'
'And your name?'
I shrugged. 'Jonathan Derry. You can check with her, if you like.' I gestured to the rank of telephones. 'She'll vouch for me.'
'Did you bring these… programs with you?'
'No,' I said. 'I thought we should make a deal first.'
'Humph.'
Behind his impassive face, a fierce amount of consideration seemed to be taking place, and at length I had a powerful feeling that he couldn't make up his mind.
I said, 'I wouldn't expect you to buy them without a demonstration. But I assure you they're the real thing.'
It produced no discernible effect. The interior debate continued; and it was resolved not by Gilbert or myself but by the arrival of someone else.
A car door slammed outside and there were footsteps on the polished parquet in the hall. Gilbert's head lifted to listen, and a voice outside the open door called 'Dad?'
'In here,' Gilbert said.
Gilbert's son came in. Gilbert's son, who had come to my house with his pistol.
I must have looked as frozen with shock as I felt: but then so did he. I glanced at his father, and it came to me too late that this was the man Sarah had described – middle-aged, ordinary, plump – who had gone to Peter's house asking for the tapes. The one to whom she had said, 'My husband's got them.'
I seemed to have stopped breathing. It was as if life itself had been punched out of me. To know what not to do…
For all my instinct that ignorance was dangerous, I had not learned enough. I hadn't learned the simple fact that would have stopped me from walking into that house: that Mr Bingo Gilbert had a marauding Italian-looking son.
It was never a good idea to pursue Moses across the Red Sea…
'My son, Angelo,' Gilbert said.
Angelo made an instinctive movement with his right hand towards his left armpit as if reaching for his gun, but he wore a bloused suede jerkin over his jeans, and was unarmed. Thank the Lord, I thought, for small mercies.
In his left hand he carried the package I had sent to Cambridge. It had been opened, and he was holding it carefully upright to save the cassettes from falling out.
He recovered his voice faster than I did. His voice and his arrogance and his sneer.
'What's this mug doing here?' he said.
'He came to sell me the computer tapes.'
Angelo laughed derisively. 'I told you we'd get them for nothing. This mug sent them. I told you he would.' He lifted the package jeeringly. 'I told you you were an old fool to offer that Irish witch any cash. You'd have done better to let me shake the goods out of her the minute her old man died. You've no clue, Dad. You should have cut me in months ago, not tell me when it's already a mess.'
His manner, I thought, was advanced son-parent rebellion: the young bull attacking the old. And part of it, I suspected, was for my benefit. He was showing off. Proving that even if I'd got the better of him the last time we'd met, it was he, Angelo, who was the superior being.
'How did this creep get here?' he demanded.
Gilbert either ignored the peacockery or indulged it. 'Mrs O'Rorke sent him,' he said.
Neither of them thought to ask the very awkward question of how I knew Mrs O'Rorke. I'd have given few chances for my health if they'd worked it through. I reckoned that this was one exceptional occasion when ignorance was emphatically the safest path, and that in prudence I should be wholly ignorant of the life and death of Chris Norwood.
'How come he still has the tapes to sell,' Angelo said cunningly, 'if he's already sent them to me?'